Modular Hydrant Nozzle Cap for Vibration Leak Detection

Solution Overview

Problem

Detecting leaks in fluid systems connected to fire hydrants is challenging due to underground location and interference from background noise, and existing leak detection systems are costly, prone to damage, and require replacement of the entire nozzle cap.

Innovation Solution

A modular nozzle cap for fire hydrants featuring a cap body with an inner metal housing and an outer non-metal housing, incorporating a vibration sensor and antenna to detect leaks, which can be easily assembled and disassembled, reducing costs and minimizing damage from pressure changes and moisture exposure.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the entire nozzle cap is replaced when components are damaged, then the leak detection system is restored, but the cost and time increase significantly

Engineering Contradiction:

Improveleak detection system functionalityVSAvoidreplacement time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The nozzle cap is divided into multiple separable components: an inner housing containing the vibration sensor, an outer housing, and a cap body. This segmentation allows individual components to be replaced independently rather than replacing the entire assembly, reducing replacement time and cost while maintaining system reliability.

Inventive Principle:

Principle #1Segmentation

2Reliability

If the entire nozzle cap is replaced when components are damaged, then the leak detection system is restored, but the cost increases significantly

Engineering Contradiction:

Improveleak detection system functionalityVSAvoidreplacement cost

Core Design Contradiction:

ReliabilityVSLoss of substance

Solution Approach 1:

The nozzle cap is divided into multiple separable components: an inner housing containing the vibration sensor, an outer housing, and a cap body. This segmentation allows individual components to be replaced independently rather than replacing the entire assembly, reducing replacement time and cost while maintaining system reliability.

Inventive Principle:

Principle #1Segmentation

3Reliability

If electronic components are housed in an enclosed cavity, then they are protected from moisture and damage, but pressure changes create stresses on structural components

Engineering Contradiction:

Improveelectronic component protectionVSAvoidstructural component durability

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The housing is divided into an inner housing containing electronic components and an outer housing that interfaces with the environment. This segmentation allows the inner housing to be protected while the outer housing absorbs pressure changes, reducing stress transmission to structural components.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The layered housing structure with inner and outer housings acts as a cushioning system that absorbs and distributes pressure changes before they reach the electronic components and structural elements, preventing damage from thermal expansion and contraction.

Inventive Principle:

Principle #11Beforehand cushioning (Prior cushioning)

4Ease of repair

If a modular design with inner and outer housings is used, then component replacement is easier and costs are reduced, but the device complexity increases

Engineering Contradiction:

Improvecomponent replacement easeVSAvoidhousing structure complexity

Core Design Contradiction:

Ease of repairVSDevice complexity

Solution Approach 1:

The nozzle cap is divided into multiple separable components: an inner housing containing the vibration sensor, an outer housing, and a cap body. This segmentation allows individual components to be replaced independently rather than replacing the entire assembly, reducing replacement time and cost while maintaining system reliability.

Inventive Principle:

Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Effectively detects leaks in fluid systems with reduced false alarms and costs, allowing for modular replacement of components rather than the entire nozzle cap, enhancing durability and maintenance efficiency.

Implementation Method 1

Leaks within the fluid systems can send vibrations through the fluid system and up the stand pipes to the fire hydrants. These vibrations propagating through the stand pipes and fire hydrants can be monitored to detect leaks within the connected fluid system.

Methodology Applied

Scientific EffectVibration detection: Vibration

Implementation Method 2

a metal insert contacting the vibration sensor and the inner housing

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Data Source

PatentUS20240369438A1Hydrant nozzle cap and method of assembling the same

Publication Date: 2024.11.07 MUELLER INT LLC

AI summary

A nozzle cap for a fire hydrant includes a cap body defining a cap axis and comprising an inner housing defining an inner fastener hole; and an outer housing defining an outer fastener hole, the outer housing axially aligned with and contacting the inner housing; and a fastener defining a head and a shaft, the shaft engaging each of the outer fastener hole and the inner fastener hole to secure the outer housing with the inner housing; a disc spring arranged on the shaft and positioned between the cap body and the head of the fastener; and a compression limiter disposed within the outer fastener hole and defining a limiter opening, wherein the shaft of the fastener further engages the limiter opening.